In certain devices, such as electrolytic capacitors, it is desirable to provide elements having effectively maximum surface area for a given mass of material. In electrolytic capacitors specifically, it is desirable to provide an anode having as great a surface area as possible so as to provide a maximum capacity for a given mass of anode material. Such anodes are conventionally formed of relatively expensive material, such as tantalum, niobium, and titanium, and, thus, the use of a minimum amount of the anode material results in the reduced cost of the capacitor.
In certain other devices, such as drilling devices, it is advantageous to use a collimated hole structure attached to drill shank wherein an abrasive slurry is pumped through the drill shank and the porous tip comprises a drill bit. The rotary or vibratory motion of the drill imparted to the abrasive slurry exuding therefrom generates the hole in a hard material. The bottom surface of a hole produced by this drill is very smooth due to use of the collimated hole passage tip that emits abrasive slurry from each passage. The bottom configuration of the hole can be formed of many geometrical shapes because the collimated hole structure tip can be fashioned into many shapes.